article: Jeff  Keith has only one leg. When he was 12 years old ,Jeff had cancer . Doctors had to cut off most of his right leg.
  Every day Jeff puts on an artificial leg. The leg is plastic. With the plastic leg Jeff can ski ,ride a bicycle ,swim and play soccer. He can also run.
  Jeff made a plan with his friends who had plastic legs, too. They decided to run across America. They all wore special T-shirts. On it was "Run ,Jeff, Run ,Jeff Keith's Run Across America."
  When he was 22 years old,Jeff  Keith ran across the United States from the east to the west. He started running in Boston. Seven  months later ,he stopped running in Los Angeles . He ran 3200 miles. Jeff wore out 36 pairs of running shoes and five plastic legs. Jeff stopped in cities on the way to Los Angeles. In every city people gave Jeff money .The money was not for Jeff ,but for American Cancer Society .The Society used the money to know more about cancer .
  On the way to Los Angeles Jeff talked to people about cancer. Jeff is disabled ,but he can do many things. He finished college and is studying to be a lawyer .Jeff says, "People can do anything they want to do .I want people to know that I ran not only for disabled people ,I ran for everybody."
question: Jeff's right leg was cut off  because of  the  _  .
options: .TB an accident cancer hurt